ISP system using non-geosynchronous orbit satellites

• US 6,985,454 B1
• Filed: 06/16/1999
• Issued: 01/10/2006
• Est. Priority Date: 01/26/1999
• Status: Expired due to Term

• Current Assignee: Globalstar Incorporated
• Original Assignee: Globalstar Incorporated
• Inventors: Wiedeman, Robert A., Waknis, Prashant V.
• Primary Examiner(s): Nguyen, Chau
• Assistant Examiner(s): Jagannathan, Melanie
• Application Number:
  US09/334,386
• Time in Patent Office: 2,400 Days
• Field of Search: 370/310, 370/311, 370312-316, 370/390, 370/394, 370/401, 370/406, 370/400, 370/402, 370/403, 370/404
• US Class Current: 370/316
• CPC Class Codes: H04B 7/18589 Arrangements for controlling an end to end session, i.e. for initialising, synchronising or terminating an end to end link

Abstract

A satellite communication system includes a plurality of satellites, such as low earth orbit satellites, and a plurality of gateways. The satellite communication system is bidirectionally coupled to a terrestrial communication system through at least the plurality of gateways. The satellite communication system and the terrestrial communications system together form a data communication network having a plurality of nodes including source nodes, destination nodes and intermediate nodes. Multiple copies of a packet can coexist within the data communication network, and the packet and its one or more copies are routed, using at least in part satellite-resident routers and gateway-resident routers, over a plurality of different paths between a particular source node and a particular destination node. At least one duplicate copy of a given packet is simply not used during the execution of a packet reordering procedure in the destination node, or at an intermediate node. Certain of the paths are carried over satellite-to-satellite cross-links, while certain other ones of the paths are carried over satellite-to-gateway uplinks and downlinks, and at least one path exists between a user terminal and at least one satellite. In a preferred embodiment the packets are TCP/IP (or equivalent protocol) packets containing information for enabling the selective destruction of a duplicate packet to occur.

Claims

1. A satellite communication system comprising:

a plurality of satellites and a plurality of gateways,

said satellite communication system being bidirectionally coupled to a terrestrial communication system through said plurality of gateways,

said satellite communication system and said terrestrial communications system comprising together a data communication network having a plurality of nodes including source nodes, destination nodes and intermediate nodes,

wherein multiple copies of a packet are selectively generated within the data communications network based on a criteria that includes at least one of (a) whether the packet was previously duplicated by a previous node, and (b) a direction of transmission, from source to destination or from destination to source,

wherein said multiple copies of a packet coexist within the data communications network and are routed, using at least in part satellite-resident routers and gateway-resident routers, over a plurality of different paths between a particular source node and a particular destination node, and

wherein at least one duplicate copy of a given packet is not used during the execution of a packet reordering procedure in the destination node, or at an intermediate node.

2. A system and network as in claim 1, wherein certain of said paths are carried over satellite-to-satellite cross-links.

3. A system and network as in claim 1, wherein certain of said paths are carried over satellite-to-gateway uplinks and downlinks.

4. A system and network as in claim 1, wherein at least one of said paths is carried over a satellite-to-user terminal uplink and downlink.

5. A system and network as in claim 1, wherein said packets are TCP/IP packets (or packets with equivalent protocol) containing information for enabling said duplicate packets to be ignored.

6. A system and network as in claim 1, wherein said plurality of gateways couple said satellite communication system to said terrestrial communication system at a plurality of points, including at least at one of regional networks, national networks, commercial networks, Internet Service Providers (ISPs), or directly to a backbone network.

7. A system and network as in claim 1, wherein said plurality of satellites comprise a constellation of non-geosynchronous orbit satellites.

8. A system and network as in claim 1, wherein said plurality of satellites comprise a constellation of low earth orbit satellites.

9. A system and network as in claim 1, wherein said plurality of satellites comprise a constellation of medium earth orbit satellites.

10. A system and network as in claim 1, wherein said packets are TCP/IP or equivalent packets.

11. A system and network as in claim 1, wherein at least some of said packets comprise voice data.

12. A system and network as in claim 11, wherein said system routes said packets comprised of voice data over semi-permanent paths that are established during the duration of a call.

13. A system and network as in claim 11, wherein said at least some of said packets that comprise voice data comprise vocoded voice data that is generated external to a user terminal and that is input to the user terminal for transmission to at least one satellite.

14. A system and network as in claim 11, wherein said at least some of said packets that comprise voice data comprise vocoded voice data that is generated internal to a user terminal for transmission to at least one satellite.

15. A system and network as in claim 1, wherein said duplicate packets are transmitted from a plurality of satellite-resident routers to a single gateway-resident router, and are injected into the Internet by the single gateway-resident router.

16. A system and network as in claim 1, wherein said duplicate packets are transmitted from a plurality of satellite-resident routers to a plurality of gateway-resident routers, and are injected into the Internet by each of the plurality of gateway-resident routers.

17. A satellite communication system comprising:

a plurality of satellites and a plurality of gateways,

said satellite communication system being bidirectionally coupled to a terrestrial communication system through at least said plurality of gateways,

said satellite communication system and said terrestrial communications system comprising together a data communication network having a plurality of nodes including source nodes, destination nodes and intermediate nodes,

wherein multiple copies of a packet are selectively generated within the data communications network based on a criteria that includes at least one of (a) whether the packet was previously duplicated by a previous node, and (b) a direction of transmission, from source to destination or from destination to source, and

wherein the multiple copies of the packet are routed, using at least in part satellite-resident routers and gateway-resident routers, over a plurality of different paths between a particular source node and a particular destination node, and

wherein at least one of the multiple copies of a packet is not used during the execution of a packet reordering procedure in the destination node, or at an intermediate node.

18. A system and network as in claim 17, wherein certain of said paths are carried over satellite-to-gateway uplinks and downlinks, and certain other paths are carried over satellite-to-satellite cross-links.

19. A system and network as in claim 17, wherein at least one of said paths is carried over a satellite-to-user terminal uplink and downlink.

20. A system and network as in claim 17, wherein said packets are TCP/IP packets (or packets with equivalent protocol) containing information for enabling said duplicate packets to be ignored.

21. A system and network as in claim 17, wherein said plurality of gateways couple said satellite communication system to said terrestrial communication system at a plurality of points, including at least at one of regional networks, national networks, commercial networks, Internet Service Providers (ISPs), or directly to a backbone network.

22. A system and network as in claim 17, wherein said plurality of satellites comprise a constellation of non-geosynchronous orbit satellites.

23. A system and network as in claim 17, wherein said plurality of satellites comprise a constellation of low earth orbit satellites.

24. A system and network as in claim 17, wherein said plurality of satellites comprise a constellation of medium earth orbit satellites.

25. A system and network as in claim 17, wherein individual ones of said packets conform to TCP/IP or an equivalent protocol.

26. A system and network as in claim 17, wherein at least some of said packets comprise voice data.

27. A system and network as in claim 26, wherein said system routes said packets comprised of voice data over semi-permanent paths that are established during the duration of a call.

28. A system and network as in claim 26, wherein said at least some of said packets that comprise voice data comprise encrypted voice data.

29. A system and network as in claim 17, wherein said multiple copies of a packet are transmitted from a plurality of satellite-resident routers to a single gateway-resident router, and are injected into the Internet by the single gateway-resident router.

30. A system and network as in claim 17, wherein said multiple copies of a packet are transmitted from a plurality of satellite-resident routers to a plurality of gateway-resident routers, and are injected into the Internet by each of the plurality of gateway-resident routers.

31. A method for packet data transmission through a data communications system comprising satellite routers and terrestrial routers, comprising steps of:

originating a stream of packets at a source node;

selectively duplicating individual ones of the stream of packets within the data communications network based on a criteria that includes at least one of (a) whether the packet was previously duplicated by a previous node, and (b) a direction of transmission, from source to destination or from destination to source;

operating said satellite routers to route duplicate packets over different paths, including wireless paths through a medium subject to transmission impairments; and

reconstructing the stream of packets from received packets while ignoring an arrival of an already received and valid packet.